Inserting Special character results in Fatal Error

I’m running LO on Windows 10 Home (64bit). LO ran fine until I installed arabic language on Win 10 and configured LO for use with Arabic. As the parallel use of Arabic and English didn’t work out ok I uninstalled arabic, deleted the LibreOffice profile folder at User/…/AppData/Roaming and reinstalled LO.
However, when I click on Insert → Special Character I get a Fatal Error and the programme aborts.
This does not happen in another account of my computer, only in my main working account.
I’d be grateful for help.